• P.S. Prieto, C.I. Briegel, R. Dysert, N. Eddy, B.J. Fellenz, E. Gianfelice-Wendt, W. Haynes, D.J. Nicklaus, R. Rechenmacher, D. Slimmer, D.C. Voy, M. Wendt
  Fermilab, Batavia
• J.C. Frisch, J. May, D.J. McCormick, J. Nelson, A. Seryi, T.J. Smith, M. Woodley
  SLAC, Menlo Park, California
• N. Terunuma, J. Urakawa
  KEK, Ibaraki

A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring is currently in progress, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital downconversion techniques, digital signal processing, also implementing a novel automatic gain error correction schema. The technical concept and realization, as well as preliminary results of the beam studies are presented.